428. MIDDLE MEDIASTINAL LYMPHADENECTOMY IN MEDIASTINOSCOPIC ESOPHAGECTOMY FOR ESCC

Abstract (Introduction) In mediastinoscopic esophagectomy, it is necessary to secure a view of the deep middle mediastinum. Although tracheal carina lymph nodes can be stably dissected using a cervical approach, but they are dissected using a hiatal approach when it is difficult to secure the field of view. (Middle mediastinum dissection) It is important to at least peel off the tracheal membrane or azygos vein in order to reduce the risk of secondary injury in the hiatal approach, even if cervical approach is difficult. In that case, the attachment between the esophagus and subcarinal tissue should be maintained for the en-block dissection. In the hiatal approach, the dissection along the pericardial and aortic surface is continuous with the dissection layer in the cervical approach and left and right tracheal cartilage are exposed enough. In the left side, the dissection along the inferior pulmonary vein is connected to the dissection of No.109L lymph node. Then, in the right side, similarly dissect the subcarinal lymph nodes along the right bronchus (No.109R lymph node). At this time, it is important to carefully check the position of azygos vein to avoid injury. Finally, the lymph nodes at the apex of the tracheal carina are sufficiently cauterized and dissected. (Conclusion) When it is difficult to reach the subcarinal tissue in cervical approach due to body type or tumor factor, the hiatal approach is necessary for sufficient lymphadenectomy of the middle mediastinum. At that case, prior detachment of the tracheal membrane and azygos vein will be important to reduce the risk of secondary injuries. Maintaining the continuity between the esophagus and dissected tissue is also important for the stable field of view.